Computers Before the widespread use of computers, managers could not make full use of large amounts of valuable information about a company's activities. The information either reached managers too late or was too expensive to be used. Today, managers are facing a wide range of data processing and information instruments. In place of a few financial controls, managers can draw on computer-based information systems to control activities in every area of their company. On any kinds of performance measures, the information provided by these systems helps managers compare standards with actual results, find out problems, and take corrective action before it is too late to make changes. The introduction of computerized information systems has sharply changed management control in many companies. Even a neighborhood shopkeeper may now use computers to control sales, billing, and other activities. In large companies, electronic data processing systems monitor entire projects and sets of operations. Now, there are about 24 million microcomputers in use in the United States—one for every 10 citizens. It is estimated that by 1996, 61 percent of American managers will be using some sort of electronic work station. In order for managers to be sure that the computer-based information they are receiving is accurate, they need to understand how computers work. However, in most cases they do not need to learn how to program computers. Rather, managers should understand how computerized information systems work how they are developed their limitations and costs and the manner in which information systems may be used. Such an understanding is not difficult to achieve. One research found that business firms were more successful in teaching basic information about computers to business graduates than they were in teaching business subjects to computer science graduates. Today, conventional financial controls are still exercised in some minor areas such as billing and vocational training.